use Win32::OLE::Variant ;
use Win32::OLE qw(in with) ;
use Win32::OLE::Const 'Microsoft Excel' ;
 
my $file = "c:/sample.xlsx" ;
 
my $Excel = Win32::OLE->GetActiveObject('Excel.Application')||Win32::OLE->new('Excel.Application','Quit');
my $Book = $Excel->Workbooks->Open( "$file") ;
my $Sheet = $Book->Worksheets(1) ;
my $chart = $Sheet->ChartObjects("Results");
$chart->Activate() ;
$chart->SeriesCollection(1)->Points(1)->Interior->{ColorIndex} = 4 ;
$chart->SeriesCollection(1)->Points(2)->Interior->{ColorIndex} = 3 ;
$chart->SeriesCollection(1)->Points(3)->Interior->{ColorIndex} = 6 ;
$Book->Save ;
$Book->Close ;